If you’ve never tried it, this week is the perfect time to taste and explore genever, a malted, juniper-forward, neutral grain-based spirit known as “the granddaddy of gin,” or sometimes as Holland or Dutch gin. Avanti Food & Beverage, Guard and Grace, Mister Tuna, Williams & Graham, the Way Back, and the Terminal Bar in Union Station are all offering special genever-based cocktails December 12 through 16.

The week of genever drinks is meant to honor Jerry Thomas, a revered figure widely regarded as America’s first celebrity bartender. Thomas “was the father of American mixology, and many of the gin-based recipes he developed—what we now call classics—were actually genever-based,” said Sean Bucalo, national educator and trade development manager for Bols Genever, one of the oldest genever brands. Bols is collaborating with multiple cities (Atlanta, Boston, Chicago, Dallas, Denver, Los Angeles, and San Francisco) nationwide on the Jerry Thomas Celebration. Thomas published the Bartender’s Guide, widely considered the first published collection of cocktail recipes, in 1862. The book includes several genever cocktails, as genever was a much more common spirit in the nineteenth century. Genever fell out of fashion as Americans began to consume more rye whiskey and gin around the turk of the century.

This week, Denver’s bartenders are bringing genever back with a range of specially crafted cocktails. Options range from Mister Tuna’s Genever Sling (genever, water, and powdered sugar) to the Way Back’s A Professional Portion (genever, Amaro Averna, Amaro Lucano, maraschino liqueur, sarsaparilla dry bitters, angostura bitters, and a flamed orange peel).

“The Denver cocktail scene has grown tremendously over the last five years, with many industry visionaries using classic standards and ingredients to inspire their bar programs,” Bucalo said. “The interest in house-made ingredients and juices, as well as bitters and other tinctures, has risen here to meet the standards Jerry set so many years ago.”

Some of those in-house ingredients will be featured in the Szechuan simple syrup in Guard and Grace’s Barrel-Aged Szechuan Old Fashioned cocktail and in the earl grey honey syrup in Terminal Bar’s Simon’s Quest cocktail, both on the menu for Denver’s Jerry Thomas Celebration week.

According to Bucalo, December is the perfect time to honor Thomas for two reasons: He died this month in 1885, and December 5 marked the anniversary of the repeal of Prohibition in 1933.

So, get out there and try something new—or at least classic—by raising a glass of genever. Jerry Thomas would approve.